After Goodell spoke at the Harvard School of Public Health and had a question-and-answer with students and faculty, he said he and NFL Players Association executive director DeMaurice Smith have been in touch on the subject of HGH. The sides agreed to implement testing as part of the collective bargaining agreement in July 2011, but they haven't been able to strike a deal on the method of testing.

"Unfortunately, we don't have that agreement," Goodell said. "I just talked to De this week about it. I still believe it's something that's in the best interest of the players, from a health and safety standpoint, but it's also in the best interest of the game. We'll have, hopefully, some meetings in the next couple weeks to address some of the remaining issues. I'm hopeful we'll get something done."

The league and the players' union agreed to a population study in April, but the deal fell apart in May when the scientist selected to run the study backed out. Talks have been at a standstill since.

"It used to be that they wanted to do a population study. I think we agreed to do that," Goodell said. "Now, it's how do we execute on that and do it the right way."

Goodell said he's not frustrated with the lack of progress on the HGH front, though now it looks as if the sides will be into the third year of the CBA -- at the earliest -- before testing is implemented.

"Whenever you do something like this, you want to do it right," Goodell said. "The scientists from all over the globe have said the science is there. We should have this kind of test in place. So we're hopeful of getting it done."